This invention relates to medical apparatus and procedures.
The invention is more particularly concerned with the removal of fluid from patients' lungs.
Retention of sputum is a major cause of morbidity and mortality following thoracic surgery. The usual treatment of such conditions is by tracheostomy, that is, by making a stoma or opening through the wall of the patient's trachea and introducing a tracheostomy tube which is sealed about its outer surface with the inner surface of the trachea. The patient breathes through the tracheostomy tube which is also used as a guide for the periodic introduction of a suction catheter by which sputum can be removed from the patient's lungs.
This treatment has several disadvantages. Because the tracheostomy tube is of large diameter or is sealed with the trachea, thereby preventing airflow to the patient's mouth, he is unable to cough and clear sputum naturally. The introduction and use of the tracheostomy tube commonly causes distress and discomfort to the patient. Damage can be caused to the interior of the trachea by the use of such tubes and the opening in the wall of the trachea can take a long time to heal fully after removal of the tube.